Tough decsion. A lot depends on how many roster spots you have and what your record is so far and if this is a H2H or roto league.

If this is a league with H2H playoffs and you think your roster is good enough to get you into the playoffs already then I would roll the dice on Zbo in the hopes he can come back towards the end of the season. The way I look at it is who cares how you do in the mid part of the season, it's all about winning the leage and to do that you usually need to take risks, Zbo is a guy who if healthy could end up putting you over the top in the playoffs, I doubt Manu or Henderson will do that.